Tuyere block for metallurgical furnaces



TUYBRE BLOCK FOR METALLURGICAL FURNACES Filed Nov. 11, 1929 Patented Sept. 1, 1931 DANIEL CUSHING, OF CAMBRIDGE, MASSACHUSETTS TUYEBE BLOCK FOR METAZLURGICAL FURNACES Application filed November 11, 19.29. Serial No. 406,266.

This invention relates to a tuyere block capable of general use but particularly designed for use in a furnace for melting nonferrous scrap metal.

It is the object of my invention to provide a tuyere block of improved construction so designed that it may be readily adapted to varying operating conditions.

A further object of the invention is to provide a tuyere block having specific features by which the useful life of the block is substantially prolonged.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claim.

A preferred form of the invention and a modification thereof are shown in the drawings in which:

Fig. 1 is a sectional plan view of a furnace, showing my improved tuyere blocks in use;

Fig. 2 is a similar view showing the blocks in a different working position;

Fig. 3 is a plan view of my improved block;

Fig. i is a front elevation, looking in the direction of the arrow 4 in Fig. 3;

Fig. 5 is a side elevation, looking in the direction of the arrow 5 in Fig. 4; and

Fig. 6 is a sectional plan view of a modifi cation.

Referring to the drawings, my improved tuyere block 10 comprises a single piece of refractory material, such as carborundum, and is provided with a tuyere opening 12 formed in the body of the block and extending therethrough.

My improved tuyere block is designed particularly for use in cylindrical upright furnaces of relatively small diameter and for such purposes I preferably provide my improved block with a convex outer surface 14 'and a concave inner surface 15, said surfaces being substantially concentric with the axis of the furnace when positioned for use.

In Figs. 1 and 2, I have shown the blocks in position in a furnace having a casing 30, air supply pipes 32 and lining bricks 34 interposed between the tuyere blocks. ()no or more layers of fire bricks and fire clay are interposed between the casing 30 and the bricks 34 or tuyere blocks 10.

The inner portions 17 of the side walls of. the block are preferably beveled or inclined so that they are disposed substantially along radial lines when in position in a furnace. The outer portions 18 of the side walls of the block are preferably parallel, so that the blocks may be positioned as indicated in Fig. 1 in extreme outward position or may be moved inward as indicated in Fig. 2. In either position, the blocks are surrounded and held from movement by a packing 20 of fire clay or similar material.

This provision for radial adjustment inward or outward in the furnace is extremely important, particularly when working with non-ferrous metals, as it has been found that the blocks should be moved inward as the percentage of lead in the alloy to be melted increases. The position indicated in Fig. 1, for v instance, is suitable for working with alloys containing less than ten percent of lead,

while the position indicated in Fig. 2 is desirable when the proportion of lead is increased above ten percent.

lVith the sides'lS parallel, as indicated in the drawings, the blocks can be thus adjusted radially to any desired position, whereas if the beveled side portions 17 were continued to the full thickness of the blocks, such inward adjustment would be very closely limited.

I also find it desirable to bevel the inner portions of the top and bottom of the block as indicated at 21 and 22, so as to avoid undue obstruction to movement of the scrap metal downward past the tuyere blocks.

It is found that tuyere blocks, even when formed of highly refractory material such H as carborundum, nevertheless tend to wear somewhat rapidly around the inner end of the tuyere opening. In order to prolong the useful life of my improved tuyere blocks, I propose to provide a bushing 40 (Fig. 6) of a heat-resistant metal alloy or other suitable material which may be inserted in the tuyere block 42 to reduce the wear around the tuyere openin D f the bushing 40 becomes worn or burned,

it can be easily removed and replaced Without destroying the entire block. To permit such removal and replacement, I preferably form the bushing of conical shape with the larger end outward so that it may be securely held in place but may be easily driven out by blows delivered at the inner end of the bushing.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claim, but what I claim is A tuyere block adapted to form an integral part of a metallurigical furnace wall and comprising a single piece of refractory material having a tuyere opening formed therethrough and having inner portions of the side walls ofsaid block substantially radial of the furnace when the block is in position for use and the outer portions of the side Walls being parallel and permitting inward and outward adjustment of said block relative to the axis of the furnace. V

In testimony I have hereunto affixed my signature.

DANIEL CUSHING. 

